<!DOCTYPE html>
<html lang="en">
   <head>
      <meta charset="UTF-8">
      <title>for循环</title>
   </head>
   <body>
      <script>
         let sum = 0;
         for (let i = 1; i <= 100; i++) {
            if (i % 2 === 0) {
               sum += i
            }
         }
         document.write(`1~100之间偶数的和:${sum}`)
      </script>
   </body>
</html>